I have just been trying to find out the year of my Ty 175,to find that the engine number looks like it has been ground off and the frame number reads * 13 E - 000284* . I found a chart on the net and it looks like it might actually be a 125 frame. How would I check the engine cc without a number.? And I am correct in saying that the frame is a 125?

Cheers

you could take the cylinder head off and measure the diameter of the bore. TY175 standard bore is 66mm diameter

If you have a clever way of measuring, you could alternatively either take off the exhaust pipe or the reed cage and measure the bore

The TY175 and TY125 have the same stroke

Lots of TY125s have been made into 175s over the years

Edited July 8, 201313 yr by feetupfun

If you are still having problems identifying the motor, post some photos showing the engine covers, cylinder and head

Thanks for the info, when you say take pics of the cylinder and head do you require me to take off the cylinder head, I suppose you must do to see the cylinder ?

Not necessary the dimension of the cylinder is normally easy to detect as the cubic cc is printed on the cylinder from the outer side!

You find in near the intake on the left side (in driving direction),

if it is a 125 cc model there should be printed 123 cc

If it is a 175 cc model there should be printed 171 cc

It is not possible to rebore the 123cc cylinder to a 171cc piston!

See here:

Edited July 8, 201313 yr by pschrauber

Just forgot the frame of the 125 cc and the 175 cc model are pretty much the same.

Great advice thanks, checked where you said ait as 171 stamped on the engine.

Thanks

Such a sweet little motor! Pity we cannot have something like that nowadays for punters and beginners bikes! On a modernized chassis this would be superb!

Such a sweet little motor! Pity we cannot have something like that nowadays for punters and beginners bikes! On a modernized chassis this would be superb!

Somebody who was supposedly in the know told me that Yamaha was considering reproducing the engine in a 200 version, no mention of a new frame. Anyone else heard any rumours ?